A new Cochrane review has found no clear evidence for cannabis-based medicines work for chronic neuropathic pain
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There is no clear evidence that cannabis-based medicines provide pain relief for chronic neuropathic pain, an updated Cochrane review finds.
Chronic neuropathic pain is caused by nerve damage. Existing medications help only a minority of patients, driving interest in alternatives, such as cannabis-based medicines. These can include herbal cannabis or isolated ingredients of the cannabis plant such as tetrahydrocannabinol (THC) by inhalation, mouth sprays, tablets, creams, and patches placed on the skin.
Researchers reviewed 21 clinical trials involving more than 2100 adults, comparing cannabis-based medicines with placebo over periods of two to 26 weeks.
Cannabis-based medicines were grouped into three types: products which contain mostly THC, the psychoactive component of cannabis; products which contain mostly cannabidiol (CBD), a non-intoxicating compound; and balanced THC/CBD products, which contain similar amounts of both.
The review found no high-quality evidence that cannabis-based medicines reduce neuropathic pain more than placebo across the three types of medicines. While some small improvements were reported by patients using products with both THC and CBD, these changes were not large enough to be considered clinically meaningful.
Reporting of adverse events was not consistent across the included trials, so certainty around side-effects was low to very low across all types of cannabis-based medicines. Products containing THC were associated with increases in symptoms such as dizziness and drowsiness, with a potential increase in the number of people withdrawing from trials due to side effects.
Clinician and review author from Technische Universität München and Medical Center Pain Medicine and Mental Health Saarbrücken, Winfried Häuser, emphasized the need for better quality studies:
We need larger, well-designed studies with a treatment duration of at least 12 weeks that include people with comorbid physical illnesses and mental health conditions to fully understand the benefits and harms of cannabis-based medicines. At present, the quality of most of the trials is too poor to draw firm conclusions.
— Winfried Häuser, clinician and author
The authors conclude that the evidence remains weak and uncertain, underscoring the need for higher-quality research before cannabis-based medicines can be recommended for chronic neuropathic pain.
#InsideTheBox is a column by Dr Andy Gray, a pharmaceutical sciences expert at the University of KwaZulu-Natal and Co-Director of the WHO Collaborating Centre on Pharmaceutical Policy and Evidence Based Practice. (Photo: Supplied)
By Andy Gray
There has been much confusion and misunderstandings about how cannabis and associated products are regulated in South Africa, with government’s own missteps adding to the uncertainty. In his last #InsideTheBox column for the year, Dr Andy Gray clearly sets out the current legal and regulatory situation and where we’re heading.
There is a fundamental assumption that underpins much of the legislation relating to pharmacologically active substances, especially those that have neuropsychiatric effects. Some are recognised as having legitimate medicinal uses, in humans and/or animals, and so are regulated as medicines. Others are deemed to have no legitimate medicinal uses, and so their possession and use is prohibited or even criminalised. Some of these substances are obtained from natural sources, such as plants or fungi, and some have been recognised and used since antiquity, precisely for their effects, both for pleasure and ritual.
Cannabis is a prime example, which grows on all continents other than Antarctica and has been used for a wide variety of purposes, both for its pharmacological actions and for its physical attributes, as a source of fibre and nutrition.
South Africa has a long and complex history with regard to cannabis. It was the South African government which proposed to the League of Nations Dangerous Drugs Committee in 1923 that cannabis be subjected to international regulation. That status remains in place, in terms of the Single Convention on Narcotic Drugs, 1961, to which South Africa is a signatory. Schedule I to the Convention, which is maintained by the International Narcotics Control Board, includes “the flowering or fruiting tops of the cannabis plant”, as well as “the separated resin, crude or purified, obtained from the cannabis plant”. Parties to the Convention are required to “adopt such measures as may be necessary to prevent the misuse of, and illicit traffic in, the leaves of the cannabis plant”. Cultivation of cannabis is to be regulated in the same manner as that applied to opium poppies, but with an important caveat: “This Convention shall not apply to the cultivation of the cannabis plant exclusively for industrial purposes (fibre and seed) or horticultural purposes.”
As a result, cannabis was for many years listed as a Schedule 7 substance in terms of South Africa’s Medicines and Related Substances Act, 1965, and also included in the “Undesirable Dependence-Producing Substances” in terms of the Drugs and Drug Trafficking Act, 1992. While exceptional access was allowed for research, analysis or use by a particular patient, substances in those categories could not ordinarily be possessed or sold.
That entire legal construct was overturned by a 2018 Constitutional Court judgment which declared the relevant sections of both laws unconstitutional “to the extent that they criminalise the use or possession in private or cultivation in a private place of cannabis by an adult for his or her own personal consumption in private”. The court allowed legislators a period of 24 months to remedy the situation.
THC and CBD
Although the cannabis plant contains over 100 identifiable chemical components, two are of particular importance. Tetrahydrocannabinol (THC) is the psychoactive component, whereas cannabidiol (CBD) is not psychoactive. At higher doses, cannabidiol has been shown to be effective in the management of some paediatric epilepsy syndromes.
The first change made to comply with the Constitutional Court judgment involved moving THC to Schedule 6 (alongside morphine, for example) and CBD to Schedule 4 (as a prescription medicine). The Schedule 6 inscription also included an exception to allow adult use, echoing the wording in the court judgment. The control measures applicable to a Schedule 6 substance (such as the need for a prescription) do not apply when “raw cannabis plant material is cultivated, possessed and consumed by an adult, in private for personal consumption”. The Schedule 4 inscription also allowed for low-dose CBD products (containing a maximum of 20mg per day and 600mg per pack) to be regulated as a complementary medicine, provided the labelling made only a low-risk claim (a general health enhancement or health maintenance claim or a claim of relief from minor symptoms).
The South African Health Products Regulatory Authority (SAHPRA) has issued just over a hundred licences for the cultivation and export of cannabis for medicinal purposes. These licences are for the preparation of the raw material from which medicines could be made, but no THC-containing products have yet been registered in South Africa. SAHPRA does not report on the number of section 21 permits issued to individual patients seeking access to THC-containing medicines, nor on the sources of unregistered medicines approved in that manner (section 21 permits allows for access to medicines not registered by SAHPRA).
SAHPRA’s cannabis cultivation permits do not allow the sale of cannabis products directly to the public. SAHPRA has not issued licences to any retail outlets for cannabis or cannabis-containing products. Retail outlets claiming to be licensed “dispensaries” are therefore operating illegally.
In 2024, the Schedules were again updated, with this exception inserted: “in raw cannabis plant material cultivated and possessed in accordance with a permit issued in terms of the Plant Improvement Act (Act 11 of 2018) and processed products manufactured from such material, intended for agricultural or industrial purposes, including the manufacture of consumer items or products which have no pharmacological action or medicinal purpose”.
The Plant Improvement Act, 2018, is intended to regulate the propagation and sale of particular plants, setting quality standards for economically important varieties, such as wheat. In November 2025, the Minister of Agriculture, Land Reform and Rural Development issued regulations in terms of this Act, setting a THC limit of 2% for the leaves and flowering heads of cannabis plants considered to be “hemp” (low-THC cannabis). That action provides the clarity required to interpret the Schedules to the Medicines Act and creates a process for the issuing of “hemp” permits for the cultivation and sale of low-THC cannabis for industrial applications.
‘A work in progress’
Bringing the Drugs and Drug Trafficking Act into alignment with the Constitutional Court judgment has been far more complex than the Medicines Act and is still a work in progress. The section of the Drugs Act which enabled the Minister of Justice to make schedules listing substances in different categories was found to be unconstitutional in 2020. Future changes to the schedules will require an Act of Parliament. Distinct from the Schedules to the Medicines Act, these lists designate which substances, for example are considered “Undesirable Dependence-Producing Substances”, the possession of which may be a criminal offence.
Instead, the Minister of Justice and Correctional Services tabled a separate Bill in 2019, which was finally passed as the Cannabis for Private Purposes Act, 2024. While that Act has been assented to by the President, it has not yet been promulgated and no regulations have been issued. The legislation is therefore not yet in operation. Regulations are needed, for example, to specify the amounts of cannabis that can be cultivated, possessed or transported. Most importantly, though enabling the possession or cultivation of cannabis in a private place, and therefore personal consumption by an adult, the Act does not enable the commercialisation of cannabis for “recreational” or “adult use”, as is the case with alcoholic beverages or tobacco products.
South Africa’s Cannabis Master Plan, which envisages three separate value chains, covering medicinal cannabis, hemp, and adult use, is now being driven by the Department of Trade, Industry and Competition (DTIC). The DTIC plans to submit a Hemp and Cannabis Commercialisation Policy to Cabinet by April 2026 and to table an Overarching Cannabis Bill by mid-2027.
The 2018 Constitutional Court judgment overturned almost a century of established practice. While the evidence for the medicinal value of cannabis and specific cannabinoids is still scanty, the assumption that such products have no medicinal value at all is no longer tenable. As with all pharmaceutical products, this is a highly regulated market with high barriers to entry.
An industrial market for low-THC cannabis is already well established and the necessary steps to enable its growth are now in place. However, the ill-informed ban on the inclusion of any cannabis components in foodstuffs, which was issued and then rapidly repealed in 2025, is indicative of the lack of coherence in government policy. The challenge remains the commercialisation of an adult use market, and whether that will enable the involvement of the small-scale rural growers who have traditionally met demand for the product.
Cannabis policy therefore remains in flux, and the entire legislative process has been marked by missteps, missed steps, reverses, ambivalence and confusion. Some pieces of the picture are in place, but others remain uncertain or incomplete.
*Dr Gray is a Senior Lecturer at the University of KwaZulu-Natal and Co-Director of the WHO Collaborating Centre on Pharmaceutical Policy and Evidence Based Practice. This is part of a series of #InsideTheBox columns he is writing for Spotlight.
Disclosure: Gray serves on three technical advisory committees at the South African Health Products Regulatory Authority and previously chaired the Cannabis Working Group.
Note: Spotlight aims to deepen public understanding of important health issues by publishing a variety of views on its opinion pages. The views expressed in this article are not necessarily shared by the Spotlight editors.
Patients prescribed medicinal cannabis in Australia maintained improvements in overall health-related quality of life (HRQL), fatigue, and sleep disturbance across a one-year period, according to a study published April 2, 2025, in the open-access journal PLOS One by Margaret-Ann Tait from The University of Sydney, Australia, and colleagues. Anxiety, depression, insomnia, and pain also improved over time for those with corresponding health conditions.
Research into the therapeutic benefits of medicinal cannabis has increased since the discovery of the analgesic properties in cannabis plant compounds. In 2016, advocacy groups lobbied the Australian government to bring about legislation changes that allow patients who were not responding to conventional treatment to access medicinal cannabis with a prescription from clinicians. More than one million new patients in Australia have received medicinal cannabis prescriptions for more than 200 health conditions.
A multicenter prospective study called the QUEST initiative (QUality of life Evaluation STudy) recruited adult patients with any chronic health condition newly prescribed medicinal cannabis oil between November 2020 and December 2021. Tait and colleagues gathered 12-month follow-up data to determine if previously reported improvements at three months would be maintained long-term. Of 2744 consenting participants who completed baseline assessments, 2353 also completed at least one follow-up questionnaire and were included in analyses, with completion rates declining to 778/2353 (38%) at 12 months. Participants with clinician-diagnosed conditions completed questionnaires covering condition-specific symptoms, and HRQL, which encompasses physical, emotional, social, and cognitive function, as well as bodily discomfort.
The researchers found that short-term improvements in overall HRQL reported at three months were maintained over a 12-month period in patients prescribed medicinal cannabis in Australia. People with chronic health conditions reported improvements in fatigue, pain, and sleep. Patients with anxiety, depression, insomnia, or chronic pain diagnoses also showed improvements in condition-specific symptoms over 12 months. Patients treated for generalized anxiety, chronic pain, insomnia, and PTSD all showed improvements in HRQL. Participants with movement disorders had improved HRQL but no significant improvements in upper extremity function scores.
The study was large enough to assess patients across a wide range of chronic conditions and socio-demographics in a real-world setting. However, without a control group, it was not possible to confidently attribute changes over time to medicinal cannabis.
Despite this limitation, the results suggest that prescribing medicinal cannabis to patients with chronic health conditions may improve pain, fatigue, insomnia, anxiety, and depression and overall HRQL. The findings also suggest that any improvements would be apparent quickly and maintained long-term. According to the authors, the results from this study contribute to the emerging evidence base to inform decision making both in clinical practice and at the policy level.
The authors add: “This is promising news for patients who are not responding to conventional medicines for these conditions.”
A lesser-known cannabinoid that is gaining in popularity, Cannabigerol (CBG), was shown to effectively reduce anxiety in a clinical trial – without the intoxication typically associated with whole plant cannabis. It may even have some memory enhancing effects, according to a new study in Scientific Reports.
For the study, Carrie Cuttler, an associate professor of psychology at Washington State University, and colleagues conducted the first human clinical trial investigating the acute effects of CBG on anxiety, stress and mood.
The research revealed that 20mg of hemp-derived CBG significantly reduced feelings of anxiety at 20, 45 and 60 minutes after ingestion compared to a placebo. Stress ratings also decreased at the first time point compared to the placebo. The findings align with survey data from a previous study led by Cuttler that indicated 51% of CBG users consume it to decrease anxiety, with 78% asserting its superiority over conventional anxiety medications.
“CBG is becoming increasingly popular, with more producers making bold, unsubstantiated claims about its effects,” Cuttler said. “Our study is one of the first to provide evidence supporting some of these claims, helping to inform both consumers and the scientific community.”
For the study, Cuttler’s team at WSU and colleagues at the University of California, Los Angeles, conducted a double-blind, placebo-controlled, experimental trial with 34 healthy cannabis users. The participants completed two sessions over Zoom during which they provided baseline ratings of their anxiety, stress and mood.
They then ingested either 20mg of hemp-derived CBG or a placebo tincture mailed to them ahead of time. The participants then rerated their mood, stress, anxiety and other variables such as feelings of intoxication and whether they liked how the drug made them feel at three different time points post-ingestion. Additionally, they reported on potential side effects like dry eyes and mouth, increased appetite, heart palpitations and sleepiness.
The sessions were repeated a week later with the participants taking the alternate product prior to completing the same assessments. The design ensured that neither the participants nor the research assistants knew which product was administered.
Surprising outcomes
One of the most surprising outcomes was CBG’s effect on memory. Contrary to expectations based on THC’s known effects on memory, CBG significantly enhanced the ability to recall lists of words. Participants were able to recall more words after taking 20mg of CBG than after taking a placebo.
“We triple-checked to ensure accuracy, and the enhancement was statistically significant,” Cuttler said.
Furthermore, the study found that CBG did not produce cognitive or motor impairments, or other adverse effects commonly associated with THC, the psychoactive ingredient in cannabis. Participants in the experimental group reported low intoxication ratings and minimal changes in symptoms like dry mouth, sleepiness and appetite. Contrary to previous self-report surveys where users touted CBG’s antidepressant effects, the participants in the current study did not report significant mood enhancement after taking CBG.
While the research is promising, Cuttler cautions the results should be interpreted carefully due to the study’s limitations. The use of experienced cannabis users, the modest dose of CBG and the timing of assessments might have influenced the findings. Additionally, the study’s remote nature, conducted via Zoom, and lack of physiological measurements further constrain the conclusions.
“We need to avoid claims that CBG is a miracle drug. It’s new and exciting, but replication and further research are crucial,” Cuttler said. “Ongoing and future studies will help build a comprehensive understanding of CBG’s benefits and safety, potentially offering a new avenue for reducing feelings of anxiety and stress without the intoxicating effects of THC.”
Moving forward, Cuttler and her team are designing a new clinical trial to replicate their findings and include physiological measures such as heart rate, blood pressure and cortisol levels. They also plan to extend the research to non-cannabis users. Additionally, Cuttler is planning a study on CBG’s effects on menopause symptoms in women.
New research shows Australian healthcare practitioners are often prescribing medicinal cannabis for psychiatric conditions where the evidence for effectiveness is unclear. But researchers who looked into the prescribing data believe that perhaps something has been overlooked, possibly leading to new avenues for treatment. The findings come University of Sydney researchers and are published in Frontiers in Pharmacology.
“These data confirm many Australians have unmet needs around their mental health and that medicinal cannabis is now frequently being trialled as an alternative to conventional therapies,” said study leader Dr Elizabeth Cairns.
“Medicinal cannabis is not typically prescribed as a first-line therapy, so those using it for conditions such as anxiety and depression likely have not had success with other treatments.
“This provides us with new leads for our clinical trials that will hopefully produce high-quality evidence to support or discourage current patterns of use.”
Dr Cairns and colleagues analysed the complete record of medicinal cannabis prescribed through Special Access Scheme B (SAS-B), using data supplied by the Australian Therapeutic Goods Administration (TGA) going back to the drug’s legalisation there in 2016, which allowed a diverse range of CBD and THC products to be legally available for medical use.
Prescriptions through this scheme have been increasing annually since the drug made its way into Australia’s pharmaceutical market in late 2016. From February 2021 the number of prescriptions started to boom, leaping from 100 000 to 300 000 by September the following year.
After treatment for chronic pain, analysis by the Lambert researchers shows anxiety is the second most common condition being treated with prescribed medicinal cannabis in Australia. However, evidence for the effectiveness of medicinal cannabis products in treating anxiety is surprisingly poor.
There is also increasing prescribing for conditions such as depression, ADHD and autism where an “evidence gap” exists around effectiveness.
Psychiatric prescriptions, used to treat mental, emotional, developmental and behavioural disorders, make up 33.8% of total approvals.
“Despite prescribing for a variety of different psychiatric indications, there is limited published high-quality evidence of efficacy to support this prescribing,” Dr Cairns said.
“The key here is not that the evidence shows cannabis products don’t work, more that high-quality studies supporting current prescribing just haven’t been done.”
Medicinal cannabis has been approved for anxiety disorders far more than any other psychiatric condition, making up 22.6% of all SAS-B prescriptions, and the type of medications used to treat anxiety caught the interest of scientists at Lambert.
“The anxiety data are really interesting because more than three quarters of the products prescribed contain THC (tetrahydrocannabinol), but THC is often thought of as anxiety-inducing, with cannabis use sometimes associated with paranoia and social anxiety,” Dr Cairns said.
“It makes you think, is there something about THC that we’ve missed historically?”
Dr Cairns suggested more priority research funding is needed to examine the effectiveness of medicinal cannabis products at improving mental health and quality of life.
The researchers said healthcare professionals often struggle to find reliable information about prescribing the hundreds of medicinal cannabis products available, and whether THC or CBD products are best used for different psychiatric conditions.
Cannabis’s pain reduction effects appear to be less effective than previously though. Photo by Kindel Media
Cannabis product use provides modest, short-term improvements in chronic pain, albeit with some side effects, according to a large review of research on cannabis pain management. The review also revealed a general lack of high quality evidence such as randomised controlled trials (RCTs). The data will be uploaded to a web app made by Oregon Health & Science University to inform clinicians on cannabis medications.
Reporting in Annals of Internal Medicine, researchers found evidence to support a short-term benefit in treating neuropathic pain with two synthetic products with 100% tetrahydrocannabinol (THC): dronabinol (under the trade name Marinol) and nabilone (Cesamet). Another product, a sublingual spray of equal parts THC and cannabidiol (CBD), known as nabiximols, also showed evidence of some clinical benefit for neuropathic pain. All of the products had side effects, such as nausea, sedation and dizziness.
From 3000 studies, the researchers selected RCTs or comparative observational studies of patients with chronic pain that compared cannabis products with a placebo or no treatment (that is, usual care) for at least 4 weeks of treatment or follow-up.
They ended up with a total of 25 with scientifically valid evidence – 18 RCTs and seven observational studies. Cannabinoids were categorised as high, comparable, or low THC-to-CBD ratio. The researchers found:
Synthetic products with high THC (> 98%) and little or no CBD: moderate improvement in pain, but greater sedation risk and possible increase in dizziness
Extracted products with majority THC (THC:CBD ratio ranging from 3:1 to 47:1): no significant improvement in pain, but greater study withdrawal because of adverse events and dizziness
Sublingual sprays with comparable THC and CBD levels: small improvement in pain but a much greater increased risk of dizziness and sedation and a moderate increase in nausea
Besides these findings, there was little evidence to support any other conclusions.
“In general, the limited amount of evidence surprised all of us,” said lead author Marian S. McDonagh, PharmD, emeritus professor at OHSU. “With so much buzz around cannabis-related products, and the easy availability of recreational and medical marijuana in many states, consumers and patients might assume there would be more evidence about the benefits and side effects.
“Unfortunately, there is very little scientifically valid research into most these products. We saw only a small group of observational cohort studies on cannabis products that would be easily available in states that allow it, and these were not designed to answer the important questions on treating chronic pain.”
“For some cannabis products, such as whole-plant products, the data are sparse with imprecise estimates of effect and studies had methodological limitations,” the authors noted.
This situation makes it difficult to guide patients.
“Cannabis products vary quite a bit in terms of their chemical composition, and this could have important effects in terms of benefits and harm to patients,” said co-author Roger Chou, MD. “That makes it tough for patients and clinicians since the evidence for one cannabis-based product may not be the same for another.”
The living review, including a visual abstract summary of the findings, will also be shared on a new web-based tool launched by OHSU and VA Portland Health Care System early this year to help clinicians and researchers evaluate the latest evidence around the health effects of cannabis. Known as Systematically Testing the Evidence on Marijuana, or STEM, the project includes ‘clinician briefs’ to help health care workers translate the clinical implications.
“This new living evidence review is exactly the type of resource clinicians need to clarify for patients the areas of potential promise, the cannabis formulations that have been studied and, importantly, the major gaps in knowledge,” said co-author Devan Kansagara, MD, MCR, professor of medicine at OHSU.
A study found that access to medical marijuana to treat pain, anxiety, or depression symptoms led to cannabis use disorder (CUD) in a significant minority of individuals while failing to improve their symptoms. The Massachusetts General Hospital (MGH) study was published in JAMA Network Open.
In the US, individuals are able to gain access to cannabis products using medical marijuana cards (MMCs), usually issued by a doctor. Researchers found the greatest risk of developing the addictive symptoms of CUD was in those seeking relief from anxiety and depression. This finding indicates the need for stronger safeguards over the dispensing, use, and professional follow-up of people who legally obtain cannabis through MMCs.
“There have been many claims about the benefits of medical marijuana for treating pain, insomnia, anxiety and depression, without sound scientific evidence to support them,” said lead author Jodi Gilman, PhD, with the Center for Addiction Medicine at MGH. “In this first study of patients randomised to obtain medical marijuana cards, we learned there can be negative consequences to using cannabis for medical purposes. People with pain, anxiety or depression symptoms failed to report any improvements, though those with insomnia experienced improved sleep.”
Dr Gilman was particularly disturbed by the fact that individuals with symptoms of anxiety or depression – the most common conditions which people seek medical cannabis for – were the ones most vulnerable to developing cannabis use disorder. CUD symptoms include a vicious circle of needing more cannabis because of growing tolerance, and seeking out cannabis to treat the psychological problems it causes.
“Medical” cannabis has surged in popularity in the US, as so far 36 of its 50 states have commercialised its use for myriad health conditions through medical marijuana cards. These cards require written approval of a licensed physician who, under the current system, is often not the patient’s primary care provider but rather a ‘cannabis doctor’ who may provide authorisation to patients with only a cursory examination, no recommendations for alternative treatments, and no follow-up. The medical marijuana industry effectively functions outside the regulations that apply to most fields of medicine.
The researchers started their trial in 2017 with 269 adults (average age of 37) who were interested in obtaining a medical marijuana card. One group was allowed to get MMCs immediately, while the second group, designed to serve as a control, was asked to wait 12 weeks before obtaining a card. Both groups were tracked over 12 weeks. The team found that the odds of developing CUD were nearly two times higher in the MMC cohort than in the wait list control group, and that by week 12, 10% of the MMC group had developed a CUD diagnosis, with the number rising to 20% in those seeking a card for anxiety or depression.
“Our study underscores the need for better decision-making about whether to begin to use cannabis for specific medical complaints, particularly mood and anxiety disorders, which are associated with an increased risk of cannabis use disorder,” said Dr Gilman. Regulation and distribution of cannabis to people with medical marijuana cards needs to be greatly improved, no matter the specific condition they are issued for. “There needs to be better guidance to patients around a system that currently allows them to choose their own products, decide their own dosing, and often receive no professional follow-up care.”
Due to the sizeable interest in the use of cannabis-based medications in treating drug resistant epilepsy and comparative lack of clinical guidance on prescription, an expert working group in Australia recently developed an interim “consensus advice” for prescribers and published it in the British Journal of Clinical Pharmacology.
The working group was made up of paediatric and adult epilepsy specialists, clinical pharmacists, pharmacologists, and cannabis researchers. Epilepsy occurs in 1–2% of the population, and about one in three people with epilepsy are considered drug resistant to standard antiseizure medications.
Since there are few clinical data available on comparative efficacy of cannabinoids with registered epilepsy treatments, the authors recommend cannabinoids only in drug resistant epilepsy, in carefully selected compliant patients with specific epilepsy phenotypes.
The document provides an overview of the different cannabis medicines currently available for treating epilepsy in children and adults, with information on dose, drug interactions, toxicity, and type and frequency of symptom and seizure relief. The consensus advice will be updated as new evidence emerges and will provide the structure for a more definitive guideline in the future.
“In the absence of a registration dossier, scientific experiments and case reports are helpful to provide some guidance to optimised dosing. However as in this guidance, observational data obtained from clinical practice – which often includes information not included in scientific experiments or even early clinical trial data, such as treating patients with other comorbidities, taking multiple medications, and patient diversity – can be very helpful to clinical practice,” said senior author Jennifer H. Martin, MBChB, MA, PhD, FRACP, a researcher at the University of Newcastle and the Director of the Australian Centre for Cannabis Clinical and Research Excellence.
